package com.homework3;


import java.util.HashMap;
import java.util.Map;

public class Test02 {
    public static void main(String[] args) {
        Map<Object, Object> objectObjectMap = new HashMap<>();
        objectObjectMap.put("及时雨", "宋江");
        objectObjectMap.put("玉麒麟", "卢俊义");
        objectObjectMap.put("智多星", "吴用");
        objectObjectMap.put("入云龙","公孙胜");
        objectObjectMap.put("豹子头","林冲");
        objectObjectMap.remove("玉麒麟");
        objectObjectMap.put("智多星","null");
        Object old = objectObjectMap.remove("及时江");
        objectObjectMap.put("呼保义",old);
    }
}
